I've been down this road several times, and my recommendation is Folyo (http://www.folyo.me/)
I've tried Dribbble, but half of the people available "for hire" are moonlighting (not ideal and wound up with a lot of false starts) and when I put an ad on Authentic Jobs, I was flooded with extremely unqualified applicants.
I also tried Scoutzie and that was the worst of all of them, because it requires you to comb through a bunch of portfolios, and most weren't very good, and the filters weren't specific enough for skillsets.
I've tried Dribbble, but half of the people available "for hire" are moonlighting (not ideal and wound up with a lot of false starts) and when I put an ad on Authentic Jobs, I was flooded with extremely unqualified applicants.
I also tried Scoutzie and that was the worst of all of them, because it requires you to comb through a bunch of portfolios, and most weren't very good, and the filters weren't specific enough for skillsets.